svelma VS svelte-headlessui

I don't know. On the Github page it says "If you are doing server-side rendering with Sapper (or SvelteKit), you'll need to import the .svelte files directly so that your app can compile them, rather than importing from the compiled module." And there is an open issue for SvelteKit. It says:

Svelma is good: https://github.com/c0bra/svelma

As a side note, my project was the first to be published under the name svelte-headlessui and is both more popular and more complete than the other project. I don't know why the other guy picked an identical name but it drives me a little nuts because of how unnecessarily confusing it is.

There is an unofficial Svelte port here but it doesn’t appear to be maintained so there may be a better option… that said there are a ton of better options if you want to use Tailwind with Svelte.

This and passing styles to slots, are biggest bottlenecks in wrapping components (your use case) and creating headless components (see headless ui).

Headless UI as in svelte-headlessui?

Svelte Headless UI should get some new PRs merged soon based on some comments u/ryangossiaux posted in the repo less than a week ago. He stepped away from the project for a bit after putting in a tremendous amount of work into it, and as someone who has used his library alongside Tailwinds UI on a number of projects, I’m super thankful for what he’s managed to do, and I hope that more people from the community will help support the project.

The component's come pre-styled. Styles can be overridden by tailwind classes, and here's a guide for that on the docs! If you want to use components that don't come pre-styled, I would suggest using something like Svelte Headless UI.

Just in case you haven't seen it, I ported Headless UI to Svelte recently: https://github.com/rgossiaux/svelte-headlessui

About two weeks into my first project I did purchase Tailwind UI. It is a massively useful resource, and I use it several times a week. It is a great reference tool, and is being actively added to. I have definitely recovered my initial investment in time saved. If you're using React or Vue, it is a no brainer - support if first class (along with Headless UI). I actually pivoted to SvelteKit, and started using the Tailwind UI HTML components until recently when this dropped: https://github.com/rgossiaux/svelte-headlessui. I now start with the React component.